/**
  ******************************************************************************
  * @file    stm32f4xx_cryp_des.c
  * @author  MCD Application Team
  * @version V1.4.0
  * @date    04-August-2014
  * @brief   This file provides high level functions to encrypt and decrypt an
  *          input message using DES in ECB/CBC modes.
  *          It uses the stm32f4xx_cryp.c/.h drivers to access the STM32F4xx CRYP
  *          peripheral.
  *
@verbatim

 ===================================================================
                  ##### How to use this driver #####
 ===================================================================
 [..]
   (#) Enable The CRYP controller clock using
       RCC_AHB2PeriphClockCmd(RCC_AHB2Periph_CRYP, ENABLE); function.

   (#) Encrypt and decrypt using DES in ECB Mode using CRYP_DES_ECB() function.

   (#) Encrypt and decrypt using DES in CBC Mode using CRYP_DES_CBC() function.

@endverbatim
  *
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT 2014 STMicroelectronics</center></h2>
  *
  * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
  * You may not use this file except in compliance with the License.
  * You may obtain a copy of the License at:
  *
  *        http://www.st.com/software_license_agreement_liberty_v2
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "stm32f4xx_cryp.h"


/** @addtogroup STM32F4xx_StdPeriph_Driver
  * @{
  */

/** @defgroup CRYP
  * @brief CRYP driver modules
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define DESBUSY_TIMEOUT    ((uint32_t) 0x00010000)

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/


/** @defgroup CRYP_Private_Functions
  * @{
  */

/** @defgroup CRYP_Group8 High Level DES functions
 *  @brief   High Level DES functions
 *
@verbatim
 ===============================================================================
                       ##### High Level DES functions #####
 ===============================================================================
@endverbatim
  * @{
  */

/**
  * @brief  Encrypt and decrypt using DES in ECB Mode
  * @param  Mode: encryption or decryption Mode.
  *           This parameter can be one of the following values:
  *            @arg MODE_ENCRYPT: Encryption
  *            @arg MODE_DECRYPT: Decryption
  * @param  Key: Key used for DES algorithm.
  * @param  Ilength: length of the Input buffer, must be a multiple of 8.
  * @param  Input: pointer to the Input buffer.
  * @param  Output: pointer to the returned buffer.
  * @retval An ErrorStatus enumeration value:
  *          - SUCCESS: Operation done
  *          - ERROR: Operation failed
  */
ErrorStatus CRYP_DES_ECB(uint8_t Mode, uint8_t Key[8], uint8_t* Input,
                         uint32_t Ilength, uint8_t* Output)
{
    CRYP_InitTypeDef DES_CRYP_InitStructure;
    CRYP_KeyInitTypeDef DES_CRYP_KeyInitStructure;
    __IO uint32_t counter = 0;
    uint32_t busystatus = 0;
    ErrorStatus status = SUCCESS;
    uint32_t keyaddr    = (uint32_t)Key;
    uint32_t inputaddr  = (uint32_t)Input;
    uint32_t outputaddr = (uint32_t)Output;
    uint32_t i = 0;

    /* Crypto structures initialisation*/
    CRYP_KeyStructInit(&DES_CRYP_KeyInitStructure);

    /* Crypto Init for Encryption process */
    if (Mode == MODE_ENCRYPT)    /* DES encryption */
    {
        DES_CRYP_InitStructure.CRYP_AlgoDir  = CRYP_AlgoDir_Encrypt;
    }
    else     /* if( Mode == MODE_DECRYPT )*/
    {
        /* DES decryption */
        DES_CRYP_InitStructure.CRYP_AlgoDir  = CRYP_AlgoDir_Decrypt;
    }

    DES_CRYP_InitStructure.CRYP_AlgoMode = CRYP_AlgoMode_DES_ECB;
    DES_CRYP_InitStructure.CRYP_DataType = CRYP_DataType_8b;
    CRYP_Init(&DES_CRYP_InitStructure);

    /* Key Initialisation */
    DES_CRYP_KeyInitStructure.CRYP_Key1Left = __REV(*(uint32_t*)(keyaddr));
    keyaddr += 4;
    DES_CRYP_KeyInitStructure.CRYP_Key1Right = __REV(*(uint32_t*)(keyaddr));
    CRYP_KeyInit(& DES_CRYP_KeyInitStructure);

    /* Flush IN/OUT FIFO */
    CRYP_FIFOFlush();

    /* Enable Crypto processor */
    CRYP_Cmd(ENABLE);

    if (CRYP_GetCmdStatus() == DISABLE)
    {
        /* The CRYP peripheral clock is not enabled or the device doesn't embedd
           the CRYP peripheral (please check the device sales type. */
        return (ERROR);
    }

    for (i = 0; ((i < Ilength) && (status != ERROR)); i += 8)
    {

        /* Write the Input block in the Input FIFO */
        CRYP_DataIn(*(uint32_t*)(inputaddr));
        inputaddr += 4;
        CRYP_DataIn(*(uint32_t*)(inputaddr));
        inputaddr += 4;

        /* Wait until the complete message has been processed */
        counter = 0;

        do
        {
            busystatus = CRYP_GetFlagStatus(CRYP_FLAG_BUSY);
            counter++;
        }
        while ((counter != DESBUSY_TIMEOUT) && (busystatus != RESET));

        if (busystatus != RESET)
        {
            status = ERROR;
        }
        else
        {

            /* Read the Output block from the Output FIFO */
            *(uint32_t*)(outputaddr) = CRYP_DataOut();
            outputaddr += 4;
            *(uint32_t*)(outputaddr) = CRYP_DataOut();
            outputaddr += 4;
        }
    }

    /* Disable Crypto */
    CRYP_Cmd(DISABLE);

    return status;
}

/**
  * @brief  Encrypt and decrypt using DES in CBC Mode
  * @param  Mode: encryption or decryption Mode.
  *          This parameter can be one of the following values:
  *            @arg MODE_ENCRYPT: Encryption
  *            @arg MODE_DECRYPT: Decryption
  * @param  Key: Key used for DES algorithm.
  * @param  InitVectors: Initialisation Vectors used for DES algorithm.
  * @param  Ilength: length of the Input buffer, must be a multiple of 8.
  * @param  Input: pointer to the Input buffer.
  * @param  Output: pointer to the returned buffer.
  * @retval An ErrorStatus enumeration value:
  *          - SUCCESS: Operation done
  *          - ERROR: Operation failed
  */
ErrorStatus CRYP_DES_CBC(uint8_t Mode, uint8_t Key[8], uint8_t InitVectors[8],
                         uint8_t* Input, uint32_t Ilength, uint8_t* Output)
{
    CRYP_InitTypeDef DES_CRYP_InitStructure;
    CRYP_KeyInitTypeDef DES_CRYP_KeyInitStructure;
    CRYP_IVInitTypeDef DES_CRYP_IVInitStructure;
    __IO uint32_t counter = 0;
    uint32_t busystatus = 0;
    ErrorStatus status = SUCCESS;
    uint32_t keyaddr    = (uint32_t)Key;
    uint32_t inputaddr  = (uint32_t)Input;
    uint32_t outputaddr = (uint32_t)Output;
    uint32_t ivaddr     = (uint32_t)InitVectors;
    uint32_t i = 0;

    /* Crypto structures initialisation*/
    CRYP_KeyStructInit(&DES_CRYP_KeyInitStructure);

    /* Crypto Init for Encryption process */
    if (Mode == MODE_ENCRYPT)   /* DES encryption */
    {
        DES_CRYP_InitStructure.CRYP_AlgoDir  = CRYP_AlgoDir_Encrypt;
    }
    else     /*if(Mode == MODE_DECRYPT)*/
    {
        /* DES decryption */
        DES_CRYP_InitStructure.CRYP_AlgoDir  = CRYP_AlgoDir_Decrypt;
    }

    DES_CRYP_InitStructure.CRYP_AlgoMode = CRYP_AlgoMode_DES_CBC;
    DES_CRYP_InitStructure.CRYP_DataType = CRYP_DataType_8b;
    CRYP_Init(&DES_CRYP_InitStructure);

    /* Key Initialisation */
    DES_CRYP_KeyInitStructure.CRYP_Key1Left = __REV(*(uint32_t*)(keyaddr));
    keyaddr += 4;
    DES_CRYP_KeyInitStructure.CRYP_Key1Right = __REV(*(uint32_t*)(keyaddr));
    CRYP_KeyInit(& DES_CRYP_KeyInitStructure);

    /* Initialization Vectors */
    DES_CRYP_IVInitStructure.CRYP_IV0Left = __REV(*(uint32_t*)(ivaddr));
    ivaddr += 4;
    DES_CRYP_IVInitStructure.CRYP_IV0Right = __REV(*(uint32_t*)(ivaddr));
    CRYP_IVInit(&DES_CRYP_IVInitStructure);

    /* Flush IN/OUT FIFO */
    CRYP_FIFOFlush();

    /* Enable Crypto processor */
    CRYP_Cmd(ENABLE);

    if (CRYP_GetCmdStatus() == DISABLE)
    {
        /* The CRYP peripheral clock is not enabled or the device doesn't embedd
           the CRYP peripheral (please check the device sales type. */
        return (ERROR);
    }

    for (i = 0; ((i < Ilength) && (status != ERROR)); i += 8)
    {
        /* Write the Input block in the Input FIFO */
        CRYP_DataIn(*(uint32_t*)(inputaddr));
        inputaddr += 4;
        CRYP_DataIn(*(uint32_t*)(inputaddr));
        inputaddr += 4;

        /* Wait until the complete message has been processed */
        counter = 0;

        do
        {
            busystatus = CRYP_GetFlagStatus(CRYP_FLAG_BUSY);
            counter++;
        }
        while ((counter != DESBUSY_TIMEOUT) && (busystatus != RESET));

        if (busystatus != RESET)
        {
            status = ERROR;
        }
        else
        {
            /* Read the Output block from the Output FIFO */
            *(uint32_t*)(outputaddr) = CRYP_DataOut();
            outputaddr += 4;
            *(uint32_t*)(outputaddr) = CRYP_DataOut();
            outputaddr += 4;
        }
    }

    /* Disable Crypto */
    CRYP_Cmd(DISABLE);

    return status;
}

/**
  * @}
  */

/**
  * @}
  */

/**
  * @}
  */

/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
